c# MVC 4 Web API - Return object from JSON string

Question

I'm working with the mvc 4 web api to build a service layer that will always return JSON.

My api method calls actually call another service which returns a JSON object. I then want to just pass this JSON object back as my return object, but I'm not sure what return type to use.

If I use string, it wraps the JSON object in quotes.

By the way, I already changed the default MediaTypeFormatter to be JSON.

Here is an example of the JSON object:

{
  "responseHeader":{
  "status":0,
   "QTime":0,
   "params":{
     "indent":"on",
     "q":"id:100001",
     "wt":"json"}},
  "response":{"numFound":1,"start":0,"docs":[
  {
    "Header":"Test Header",
    "MaxPrice":515.0,
    "ApartmentName":"Apartment 1",
    "MaxBathrooms":4.0,
    "Pool":true,
    "MinBathrooms":2.0,
    "MaxBedrooms":4,
    "CoveredParking":false}]
  }}

Answer 1

In the Beta release, you can use JsonValue (from the System.Json namespace). If your call to the other service returns a string which contains the JSON data, then you can call JsonValue.Parse to load that into the object to return.

In the RC release (or in the current bits from http://aspnetwebstack.codeplex.com) you can use the JToken object (from the Newtonsoft.Json.Linq namespace) - the default JSON serializer and JSON DOM are now coming from the JSON.NET library.

Answer 2

So, the issue turned out to be that I was taking a serialized json object and then reserializing in the JavaScriptSerializerFormatter that overrides the default xml MediaTypeFormatter.

I fixed the issue by returning the JsonValue and then checking the type and not reserializing it.

Thanks carlosfigueira for the help finding this.

Answer 3

To return Json from MVC, use JsonResult. You can first convert the string to an object using DataContractJsonSerializer.

http://shashankshetty.wordpress.com/2009/03/04/using-jsonresult-with-jquery-in-aspnet-mvc/